There was never a course in accessories or carry goods when I was in school. The extent of my soft-goods skill building came from years of making tiny embroidered cat and dog pillows, altering thrift store clothes, and a few DIY books from the library when I was a kid. That doesn't really make for high-quality leather work from the start.
In the summer of 2012 I was a bike commuter, hauling my groceries, gym clothes, art supplies, and everything else in an army surplus black canvas messenger bag. And that bag tore from repeated use- the strap, the corners, the strap again, until it was no longer useable.